The present invention generally relates to surgical instruments and methods of suturing tissue.
A number of diagnostic and treatment procedures are conducted intravascularly. Typically, a catheter is introduced into the vascular system at a convenient access location and is then guided to the target treatment site. The Seldinger Technique is one of the well-known early examples of this type of procedure which can include catheterization and angioplasty techniques. Procedures such as this require a vascular access. Typically an introducer sheath with or without a guide wire is inserted through a puncture wound in a vessel such as the femoral artery at a location near the groin. A catheter and other instrumentation can then be inserted through the sheath and guided to the targeted treatment site. After the diagnostic and/or treatment procedure has been completed, the puncture wound must be closed. Closing the wound can be difficult because of the substantial bleeding that can occur through an open wound in the vascular vessel. One technique for hemostasis includes applying pressure near or upstream of the puncture site. This approach suffers from many deleterious effects, not the least of which are that it can be time consuming and extremely uncomfortable—even painful—for the patient because the pressure is applied directly on or adjacent to the traumatized site. Frequently anticoagulants are employed for the original diagnostic/treatment procedures. This delays clot formation during the procedure, and this effect lasts through the initial recovery period, lengthening the time during which pressure must be applied to the wound for up to twelve hours or more. During this initial recovery period, it is imperative that the patient remain still, further adding to the patient's discomfort.
Alternatively, the puncture wound can be closed with sutures. This can be extremely difficult because the vascular vessel with the puncture lies underneath the patient's outer skin. Some vascular vessels, notably the femoral artery, appear to be relatively large; however, in practice, even the largest arteries cannot be readily sutured. Therefore, devices have been developed to facilitate subcutaneous suturing of arteries and veins. These devices can extend through the outer tissue to the puncture wound in the vascular vessel. Needles are then deployed from the device to suture the tissue adjacent the puncture wound.
Certain devices are inserted through the wound and initially deploy needles to pierce the tissue in from outside the vascular vessel and continue on into a depository in the portion of the device located within the lumen of the vessel. The suturing device can be removed from the vessel (and the patient) by withdrawing the needles and suture material at the same time. These devices leave an inverted suture path after completion of the closure. The suture material runs from the exterior tissue surrounding the puncture wound back up through the wound itself which is then tied off. Some complications may arise resulting from this type of closure, including oozing, excessive bleeding, and, on rare occasions, knot loosening. It would be preferred to provide a suturing device that allows the suture path to extend across the puncture opening internal of the vessel membrane with the suture knot overlying the exterior of the closed wound.
Furthermore, while the above-described techniques are regularly performed, as with any surgical procedure, they involve considerable risk to patients. These particular procedures entail delicate and intricate procedures. The physical condition of the patient and, importantly, the condition of the patient's vascular system can greatly impact the risks and prognosis. For example, a patient's vascular vessels may be more or less compliant. This can cause further complications making suturing of the puncture wound more difficult. Many current suturing devices cannot accommodate and support non-compliant vascular tissue because the sutures can be misplaced, not attach sufficient tissue, or pull out making wound closure more risky for these patients. Devices which can Support tissue and facilitate correct suture placement would reduce some of the risks attendant with this procedure.
In view of the above background, there remain needs for improved and/or alternative methods and devices for closing vascular opening or punctures. The present invention is addressed to these needs.